April 01, 2002

 

 Is the carbon-copy cat causing questions from your clients? - April 1, 2002

Posted on March 15, 2002

 

On Dec. 22, 2001, the first cloned kitten was born at Texas A&M University, a perfect genetic match to its donor, named Rainbow. The success story became public in mid-February when a letter describing the experiment was published in Nature and generated a flurry of press stories. Perhaps the carbon-copy cat has raised questions from your clients.

According to the 2001 national pet owner survey by the American Animal Hospital Association, eight percent of pet owners would consider cloning their pet if they had the opportunity.

Dr. Duane Kraemer, a cloning expert and part of the Texas A&M team, says that when people ask him what to expect from a clone, he emphasizes not to expect anything other than the genes and genetically determined factors to be the same.

Photos courtesy of the College of Veterinary Medicine, Texas A&M University

"This is reproduction, not resurrection," Dr. Kraemer said. "You don't get your animal back. You get closer to the animal genetically than any other way, but there are environmental and developmental factors that influence an individual." He says to think about the donor and clone as identical twins—identical twins have differences.

But, while many twins look at least physically the same, this might not hold true for your pet. The cloned cat, a female named Carbon Copy, had a coat that looked fairly different from Rainbow's coat.

Dr. Kraemer says that many clones of multicolored cats will have slightly different coats from their supposed genetic twins. Why aren't the coats identical?

Color in cats is controlled by genes that are turned on or off during fetal development, a phenomenon known as X inactivation. "That can occur at various times during development," Dr. Kraemer said. "It is uncertain what regulates them. It doesn't look like it is genetically governed, because here you have cats that are genetically identical but have different coat patterns."

While this phenomenon occurs in all multicolored cats, Dr. Kraemer says that one would expect a clone of a cat that was all one color, such as a black cat, to be an identical-looking black cat.

But are looks the most important thing? Are looks really the reason that people would even consider cloning? It is much more likely that people will want their pet back because it curled up in a ball on their lap while they were watching "Law and Order" on TV or gave their owners a high five.

Pet owners should be advised that their clone will not come equipped with a ready-made bond to them, enjoy that same toy, have that preferred perch, or carry other memories.

Most likely, however, the cat will have a personality that is similar to the one they want to revisit. Several studies of cats in the United States and England have shown this.

"In general, cats seem to have genetically determined personality types," said Dr. Katherine Houpt, director of the Animal Behavior Clinic at the Cornell University College of Veterinary Medicine. "It doesn't seem to make a whole lot of difference what the environment is. Shyness, being hostile, being friendly, being bold—they seem to be inherited."

Ralph Fisher, a Texan who runs an animal photography business, had his Brahma bull, namedChance, cloned roughly three years ago. He says the cloned bull, named Second Chance, is eerily similar. "His physical characteristics are exact," he said. "He seems to be exhibiting some of the same personality traits." The Texan says he still does a double take when he is around Second Chance.

Although Carbon Copy and Second Chance are healthy, it is important to remind clients who are thinking about re-creating their beloved pet that not all clones have been so lucky. Studies in the United States have shown that some cloned animals have been born with a variety of cardiopulmonary ailments. Japanese scientists have reported that mice they cloned died young of liver and lung problems. And then there are the numerous unsuccessful pregnancies. Many cloned farm animals have abnormal placentas, which can lead to abnormally large fetuses that don't make it to term.

The creation of Carbon Copy, funded by Genetic Savings and Clone Inc., was certainly no easy matter. The Texas A&M scientists fused 188 skin cells with cat eggs in which DNA had been removed, and created 82 cloned embryos. These embryos were transferred to wombs, but only one pregnancy resulted, and it ended in a miscarriage.

The team then made cloned embryos, using ovarian tissue cells, and transferred five of the cloned embryos to a surrogate mother cat. Only one of these made it, and the result was Carbon Copy.

Because of the lack of success with skin cells, Dr. Kraemer says that it will most likely prove easier to clone a female rather than a male cat because one can use ovarian cells to create a female. He also says that the timing of cell collection is not important. "There is no indication yet that cells from an old animal are any less useful for cloning than from a young animal," he said.

At press time, the AVMA and AAHA had not developed a position on pet cloning. The American Humane Association was still finalizing its official position but had voiced its opposition. The process itself, they said, creates a huge amount of suffering because of the number of embryos and fetuses that die in an effort to get just one clone.

The Humane Society of the United States has also been vocal about its displeasure. Millions of homeless cats and dogs are euthanatized in shelters each year, pointed out Wayne Pacelle, senior vice president of the organization. People should grieve for their deceased pet, and then learn to form a new bond with a new animal, he said, preferably a homeless one they adopt.

For some people, however, this isn't going to be quite good enough. "I just thank the Lord that I got another chance with Second Chance," Fisher said. "He has such a good attitude."

Currently, companies are not cloning pets, but owners can save their pet's genes in a bank to leave their options open. Genetic Savings and Clone Inc. offers gene banking for an initial payment of $895 and an annual maintenance fee of $100. It is uncertain exactly when, or if, pet cloning will be available on a large scale, but when available, it will be costly, perhaps on the order of $20,000.